Two girls are on either side of a tower of height 50 m. The girls observe the top of the tower at angles of elevation of 30° and 45°. If a car crosses the two girls in 20 seconds, what is the speed of the car?

• A. \(2\left( {\sqrt 3 - 1} \right)\) km/hr
• B. \(9\left( {\sqrt 3 \; + \;1} \right)\) km/hr
• C. \(7\left( {\sqrt 6 \; + \;1} \right)\) km/hr
• D. \(5\left( {\sqrt 2 - 1} \right)\) km/hr